Dynamo.



PATENTED JULY 24, 1906.

EU. KETGHUM.

DYNAMO.

APPLICATION FILED JULY 3. 1905.

4 SHEETS-SHEET 1.

lhvenfor: Ernastillchum,

PATENTED JULY 24, 1906.

E. G. KETGHUM.

DYNAMO. APPLICATION FILED JULY 3. 1905.

4 SHEETS-SHEET 2.

No. 826,668; PATENTED JULY 24, 1906. E. C. KETCHUM.

DYNAMO.

N 826,668. PATENTED JULY 24, 1906. I

E. G. KETGHUM.

DYNAMO.

- Wibwssca: ln/vmtor' mm c. ErCKctchim,

1 454 f'Q/ZAW by w UNITED STATES PATENT OFFICE.

ERNEST o. KETCHUM, OF BOSTON, MASSACHUSETTS,

' E DYNAMO.

No. seaees.

To all whom it may concern:

Be it known that I, ERNEST C. KETCHUM, a citizen of the United States of America, and a resident of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Dy- I namos, of which the following is a specification.

This invention relates to dynamo-elecw trical machines, and has for one of its objects the productionof such a machine in which the armature may be driven direct at a great velocity from high-speed motors, such as turbine-engines, without endangering the displacement of any of the elements of said armature.

tween whic an armature may be'revolved,

the said armature being composed of a plurality of disks connected inpairs by tubular members and in series by external means,

such as brushescoeperating with the periphery thereof and connected in circuit by suitable wires,

The lnvention' further consists in certain I novel features of construction and arrange ment of parts; which will be readily understood by reference to the description of the drawings and to the claims to be hereinafter given.

Of the drawings, Figure 1 represents an elevation of a machineembodying the features of this invention, together with its motor.

Fig. 2 represents a longitudinalvertical section of said machine'if" Figs, 3 ,""4,"and 5 rep- K resent, respectively, transverse vertical sections on lines 3 3, 4'4, and 5.5'on Fi .2; and Fi s. 6, 7, and 8 represent enlarged g tails 'to be ereinafter referred to. V j

Similar characters designate like arts throughout ,the several figures of the rawm s. V

n the drawings, 10" represents end pieces sup orted bsuitable legs '11 and provided wit inward y-extendin cylindrical hubs 12,-

which form coreslor po es for the field. 1nterposed betweenjandconnecting said end pieces 10 are a plurality of members 13,

Specification-of LettersPatent. Application filed m a. 1905. semi No. 268,059.

Patented July 24, 1906.

member 15, either face of which is provided with a pole 16 in alinement with each other united thereto by means of the bolts Located centrally of said members 13 is the and with the poles 12 of the end pieces 10.,

Interposed between the poles 12 and 16 and separated therefrom by suitable air-spaces is an armature 17, said armature being driven by ashaft 18 revoluble in antifriction-bearings 19 and 20, located within the chamber 21 in theend pieces 10. The bearing 20 is placed at the extreme inner face of the pole 12 to insure-support for said armature. 17 near. either end thereof. The shaft 18 is driven direct by means of a turbine-engine 22 or other'hi h-s eed motor. Screwed mto the outer en s o the chamber 21 and surrounding the shaft 18 are thrust-bearin s 23, which prevent any end movement 0 said shaft. The armature 17 is composed of a plurality of disks 24 of high magnetic permeability separated from each other by insulating-plates 2-5. The outer pair of disks 24 are mounted directly upon an insula'tin tube. 24*, secured directly to .the revoluble shaft 18, and this pair of disks is connected by a tubular member 26, extending from the inner face of one to the inner face of the other. The tubular member 26 is surrounded b." a tube of insulating material 27, upon wbic is 'mounted the next pair of disks 24, whichpair v is in turn'connected by means of a second! .tubular member surrounding the insulatingtube 27. All the pairs of disks are mounted in like manner u on the insulating-tube surrounding a meta lic tube-connector26, and

each pair is connected by ca metallic tubeconnector 26, interposed between the inner faces thereof, as better shown in Fi 6 of thedrawings. this figure, all of the disks 24are insulated As will be 'seen by re erenee to? from each other by the member 25 and are L insulated from the shaft on which they are mounted by the members 27, which members 27 also insulate the tubes 26 around the revoluble shaft 18 from each other, each tube 26 servin as a conductor between its own air of dis s 24. It is obvious that the number of disks 24 and tubes 26 may be increased indefinitely. The disks 24 are of steel and are provided with an annular peripheral band 28, of copper, which serves to conduct the current of electricity quickly to and from all portions of the periphe ofsaid disk, from center, where it flows through a tube 26.

which it moves in radial es to and from the The member is provided on either face with an insulating-plate 29, each plate being provided with studs 29*, of insulatin material, each of whichis provided witha p urality of metallic brushes 30, each of which cooperates with a copper ring 28 of one of the armature-disks 24. These brushes 30 are insulated from each other and connected by bindin -screws 31 to wires 32, which connect al of the brushes for a sin le disk with its own terminal. There are ve of these terminals 33, 34, 35, 36, and 37, mounted in %Vplate 37* of suitable insulating material.

ith the terminal 33 the wire a, leading from the left-hand disk 24, connects, and with this terminal also connects the wire g, leading from the second disk from the right'of the terminal 37, a suitable circuit.

Fig. 2. With the terminal 34 the wires 12 and f connect, and in like manner the wires 0 and 6 connect with the terminal 35. The wire (1 of theinner disk 24 of the lefthand group connects with the terminal 36. The wire it of the outer right-hand disk 24 connects with the terminal 37 It will thus be seen that by means of the wiring connecting with the terminals thus described and the connecting-tubes 26 the disks 24 are connected in series so that a current may pass successively from one of the outer disks through the wire connections to the next inner disk of the opposite group, then through the tube connecting it with its mate in the first roup, again through wire connections to t e next inner disk of' the opposite roup, and so on until the inner disk of the first-mentioned group is reached, which communicates with the terminal 36, while the outer disk of the opposite group connects with the terminal 37. A main conductingwire 38 also connects with the terminal 36 and forms with the main wire 39, leading to Each of the poles 12 is surrounded by the coils 40, connected together by the wire 41, while the opposite ends of each coil are connected, respectively, by wires 42 43 with the terminals 36 and 37. As the shaft 18 is revolved by means of the turbine 22 an electric current will be generated thereby in the field-coil which will build up the field and cause the lines of force to be materially increased as they move inwardly from the positive poles -12 to the negative poles 16, a complete circuit of these lines of force being made through the intermediate member 15 and the yokes 13 back to said poles 12.

It will be seen that as the poles are all in alinement and the armature is in alinement therewith the working parts of the armature when in operation always move in a plane at right angles to the lines of force and are constantly cutting the same without producing a reversal of the current and a change of polarity in the armature. By this arrangement whereby the movement of the armature is always at right angles to the lines of force in the field the eddy-currents and other losses which are frequent in other types of dynamos are entirely eliminated in a ma chine of this construction.

.By providing an armature in which wires are entirely dispensed with the armature is permitted to revolve at a high velocity without endangering the displacement of an of the elements which form the same. t is intended that the shaft 18 should be in perfect alinement and that the periphery of the disks forming the armature thereon should be concentric with the axis thereof. It is I evident, however, that for some reasons the shaft might get displacedand out of alinee ment or the periphery of the disks be worn at certain parts, so that a perfect contact with the brushes would not be secured when said disks are revolving at the hi h velocity essential for the proper working 0? a machine of this construction. In order to obviate this disadvantage should it occur and to. further prevent the wear of the parts as the disks revolve at high speed in contact with the brushes 30, the periphery of each of the disks is provided with a coating or thin film 44 of amalgam of mercury or similar material. This amalgam acts as a lubricant and prevents undue wear of either the brush or the annular copper ring 28 on the disk 24. As the disk revolves rapidly the brush will collect a portion of the amalgam around its end, as shown in Fig. 7, and even when pass.- ing over inequalities in the surface of said ring a perfect connection is assured at all times. This forms quite an important feature of the invention, as a perfect operation of the machine at a reat velocity is secured by this means, and the constant slapping and breaking of the circuit which would be the case when passing over inequalities in the surface of the ring 28 is obviated. As the brush passes. over the amal am it causes it to fill in any depressions in t e surface of the periphery, thereby insuring a perfectly concentric surface.

As the polarity of the armature is constant and unchanging and the flow of flux thereto from the positive poles 12 is equal, producing on either end of said armature an equal. stress, a perfectly-balanced armature is the result, which is of the greatest advantage in a machine of this type, where in order to, se-

cure eflective results'it is, essential that the armature be revolved at a greater velocity than has heretofore been believed possible. By connecting a third main to the terminal 35 a three-wire system may be operated with a single machine of this construction, which is of considerable advantage, for heretofore it has been necessary to use two dynanios when it has been desired to operatea threewire system. The formation of a chamber in the cores 12- in which bearings 19 201 are located for the shaft 18 is another advantage, as it provides a means of securing a bearing for said shaft at a point immediately adja-.

disks forming the same should have high ten-- sile strength owing to the great velocity with which they are driven. 'At the same time it is desirable that these disks be of the highest magnetic permeability, and in order to secure both of these desired results it is necessary that the disks should be formed of steel in which the carbon used will bereduced to a minimum in order to secure the desired magnetic permeabilit and that the carbon omitted from said stee be re laced with from three to five per cent; of nicke to secure the high tensile strength and elastic limit desired. This forms a very important part of the invention, as disks formed of ordinary steel or iron either are deficient in the desired magnetic permeability or the tensile stren th which is absolutely essential to the disks driven at such high velocities as is necessary to secure the roper .working of a machine of this class. he copper band 28, which is secured to the peri hery of the disks, must be brazed thereto t roughout the periphery, for any other means of securing the same to the disks would be unreliable, these disks revolving at such a rate of speed as to be liable to-dismember the bands and disconnect them from the disks.

. The dynamo shown in the drawings is par-- ticularly designed for use in connection with a single-stage impulse steam-turbine, and the armature o the dynamo is mounted directly u on the main driving-shaft without the use 0 gears or other intermediate devices.

y this construction, of machine a most powerful generator of electricity is roduced which is} capable of being driven irect by turbine-engines and other high-speed motors and which will produce a greater volta e than could be secured from machines 0 other types of reatly-increased size, thus being electrical machine, the combination of a shaft,

, para] members connecting the dlsks'in pairs, and electrlc connectlons umtmg said disks two sets of metal disks thereon, insulations between said disks, a tubular member connecting the outer disks of each set, a second tubular member surroundin the first and connecting the next pair of (llSkS, a third tubular member surrounding the second and connecting the next pair of disks, insulations between said tubular members, and external means for electrically connecting said disksv of the two sets in-series.

3. In the rotatable member of a dynamoelectrical machine,the combination of a shaft, two sets of metal disks of high magnetic permeability, insulations between the disks,

members connecting said disks in pairs, a.

cop er eripheral band secured to each of sa1 dis s, -a brush .cooperatin therewith, and means for connecting sai brushes to unite the disks in series. v i 4. In the rotatable member of a dynamoelectrical machine, the combination of ashaft, two sets of metal disks of high magnetic permeability, insulations between the dlSkS, members connecting said disks in pairs, a copper eripheral band secured to each of sa1 dis a film of mercuryu on said band,

a brush cooperating therewit and means' for connecting said brushes to unite the disks in series.

5. In'the rotatable member of a dynamoelectrical machine, the combination of a shaft, two sets of metal disks of high magnetic permeability, insulations between the dlsks, members connecting said disksin pairs, antifriction material upon the periphery of said disks, a brush cooperating therewith, and means for connecting said brushes to unite the disks in series.

6. In a dynamo-electrical machine, the combination of a field-magnet,a shaft mounted in bearings in the poles thereof, a lurality of separated metal disks-mounte therein elwith the faces ofsaid poles, tubular series.

7. In the two sets of metal disks of high magnetic permeability, insulations between the dlSkS, members connecting said disks in pairs, a film of mercury upon the periphery of said disks, a brush cooperating therewith, and means for connecting said brushes to unite the disks in series.

8. In the rotatable member of a dynamoelectrical machine, the combination of a shaft, two sets of metal disks of high magnetic permeability, insulations between the disks, members connecting said disks in pairs, a peripheral band of hlgh conductivity secured to each of said disks surrounding sald shaft, a brush cooperating therewith, and means for connecting said brushes to unite the disks in series.

rotatable member of a dynamoj electrical machine, the combination of a shaft,

9. In the rotatable member of a dynamoelectrical machine, the combination of a shaft, two sets of metal disks of high magnetic permeabilit'y, insulations between the disks, members connecting said disks inpairs, each member being shorter than that u on which I it is mounted, a peripheral band 0 hi h conductivity secured to each of said dis ssurrounding said shaft, a brush cooperatin therewith, and means for connectlng sai brushes to unite the disks in series. 10. In the rotatable member of a dynamoelectrical machine, the combination of a shaft,

two sets of metal disks of high magnetic permeability, insulations between the disks, members connectin said disks in pairs, a eripheral band of big conductivity secure to.

each of said disks surrounding said shaft, and

a brush cooperating therewith.

11. In a dynamo-electrical machine, the combination of a field-magnet provided with two poles in alinement, an intermediate pole alined therewith, insulating-disks secured to each face thereof, armature-disks revoluble between said poles, and brushes secured to saig insulating-disk and cooperating with said dis 5.

Signed by me at Boston, Massachusetts, this 30th day of June, 1905.

ERNEST C. KETCHUM.

Witnesses:

WALTER E. LOMBARD, EDNA O. CLEVELAND. 

